xref: /freebsd/share/man/man4/nvd.4 (revision 1da7f3f6f72b2245e458fc7195733268ae4a1136)
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30.\" nvd driver man page.
31.\"
32.\" Author: Jim Harris <jimharris@FreeBSD.org>
33.\"
34.Dd May 18, 2019
35.Dt NVD 4
36.Os
37.Sh NAME
38.Nm nvd
39.Nd NVM Express disk driver
40.Sh SYNOPSIS
41To compile this driver into your kernel,
42place the following lines in your kernel configuration file:
43.Bd -ragged -offset indent
44.Cd "device nvme"
45.Cd "device nvd"
46.Ed
47.Pp
48Or, to load the driver as a module at boot, place the following lines in
49.Xr loader.conf 5 :
50.Bd -literal -offset indent
51nvme_load="YES"
52nvd_load="YES"
53.Ed
54.Sh DESCRIPTION
55The
56.Nm
57driver exposes NVM Express (NVMe) namespaces as disks to the kernel disk
58storage API.
59It depends on the
60.Xr nvme 4
61driver for notification of existing NVMe namespaces and submission of NVM
62I/O commands.
63.Pp
64Device nodes from the
65.Nm
66driver will have the format /dev/nvdX and are
67.Xr GEOM 4
68disks which can be partitioned by
69.Xr geom 8 .
70Note that device nodes from the
71.Xr nvme 4
72driver are not
73.Xr GEOM 4
74disks and cannot be partitioned.
75.Sh CONFIGURATION
76The
77.Nm
78driver defines a system-wide maximum delete size for NVMe devices.
79The default is 1GB.
80To select a different value, set the following tunable in
81.Xr loader.conf 5 :
82.Bd -literal -offset indent
83hw.nvd.delete_max=<delete size in bytes>
84.Ed
85.Sh SEE ALSO
86.Xr GEOM 4 ,
87.Xr nda 4 ,
88.Xr nvme 4 ,
89.Xr geom 8 ,
90.Xr nvmecontrol 8 ,
91.Xr disk 9
92.Sh HISTORY
93The
94.Nm
95driver first appeared in
96.Fx 9.2 .
97.Sh AUTHORS
98.An -nosplit
99The
100.Nm
101driver was developed by Intel and originally written by
102.An Jim Harris Aq Mt jimharris@FreeBSD.org ,
103with contributions from Joe Golio at EMC.
104.Pp
105This man page was written by
106.An Jim Harris Aq Mt jimharris@FreeBSD.org .
107